LED current limiting

damage the LED. The simplest way to protect an LED is to include a current limiting resistor in series. LEDs have recommended operating voltage and current, based on which you can calculate the resistance using Kirchhoff's laws. EveryCircuit makes it super-easy to find the right resistance value. Launch simulation and plot LED voltage and current in oscilloscope. Then tune the resistance with the knob until LED voltage and current are optimal. LED lights up when it has enough current. It also indicates when the current exceeds the nominal by over 2x. In this circuit the nominal LED voltage and current are set to 2 V and 20 mA. I